Draft regulating apparatus for furnaces



1 1 1932. w. N. LURCOTT 1,890,296

DRAFT REGULATING' APPARATUS FOR FURNACES Filed Jan. 23, 1932 2 Sheets-Sheet 1 INVENTOR BY His Anew DRAFT REGULATING APPARATUS FOR FURNACES Filed Jan. 25, 1952 2 Sheets-Sheet 2 Z2 /8 V) 46 {6 6/6 J .56 Q /5' 2/ 20 J4 J7 T l? 44 I INVENTOR Mfr/fr ed NLU/COLZ Patented Dec. 6, 1932 UNITED STATES PATENT OFFICEY 1 WINFRELD 1v. LURcoTr, or ELIZABETH-{NEW JERSEY DRAFT REGULATING APPARATUS non FURNACES Application filed January 23,1932. Serial No. 88438.

Among the principal objects which the present invention has in view are :To provide simple and efficient means for controlling the drafts of a furnace in response to thermostatic conditions; to simplify the construe Figure 2 is a schematic view showing an end view of the apparatus and diagram of a thermostatic switch and Wiring connecting same with the draft regulating apparatus. Figure 3 is a side view of the interior of the apparatus, theside cover having beenre- 1 moved to show the interior elements.

Figure 4 is a horizontal section of the same, the section being taken as on the line 4 4 in Figure'3.

Figure 5 is a detailed view showing a fragment of a transmission element used in the motor herein described, together with a frag: ment of the engaging elements by which the 30 said transmission element is moved.

The present apparatus is employed to open and close the draft dampers under pre-arranged heat conditions desired for the furnace. With this end in view the furnace is means of ,a cable 11, the damper door 12; The v 49 weight of the door and parts connected therewith are counter-balanced by adjustable weight members 13 which usuallyslidelengthwise of the rod 9 until a balance is established. The :movement of the rod 9 is" guided by means of a bifurcated guide member 14.

' In the present apparatus the rod 9 becomes 7 what might be termed a teeter and the disturbance of its equilibrium is what the work performed depends on. To this end a yoke .5 15 forms an upwardly extending arch. The

nets 30.

lower extremities ofifthis arch are rigidlyf connected to the'rod' 9. The horizontal member of tllYOkQ 15 formsa track on which the rollers .16 travel. Therollers 16 are used to suspend the weighted casing 17 withinwhich 2 are mountedthe mechanismfor causing the said casing'to travel ba'ckand forth lengthwise. of the said yoke 15, thereby eliminating placing its weight at one side orthe other of 1 the standard 10 and so'over-balancing the rod Q 9 to open and close the door 12. a Withinthe casing is mountedftheshaft 18 upon which is mountedthe gear wheel 19. v The wheel 19.,is used to rotate the shaft 18 r andthereby turn a cra'nkQO which is rigidly 5 macheuao theisaid shaft. The crank is in turn connected-by means of a link 21 with an arm 22Tset' out, from one ofthe uprightsof, the yoke'l5; It is obviousthatas the wheel 19 andlthe' shaft 18 connected therewith rotate, thecrank 20 is swung, around in'a circle, To do this the link 21 beinganchored to the stationary arm 22to-swing thereon, results in the crank ,7

20 becoming an arm that. alternately pushes or pulls the casing [17' lengthwise of the yoke15; 1

The gear wheel 19 is driven by means of the smallpinion 23' which is fast to-a'drum 24:. The drum 24; has an extension flange 25 which is loosely engaged by thearm' '26 when-moved away fromthe magnet 30, a slot 27 being cut edgewise thereintoloosely engage the said flange 'durin'g such movement. The arm 26 is mounted upon a spring member 28 which is 3 tensioned to press the arm 26-upon the flange to frictionally engage the same. The spring 28 is connected with anarmature 29 held in p position to be operated'upon bythe magnets 250 when the same areenergized. l The slot 27. is sufficiently wide to fit the flange 25 loosely butto engage the same by beingrocked to. gripthe flange when and as" H the armature 29 is drawn toward the mag- In theforward position as shown'in Figure 18 0f the drawings, the slot 27 does-.notjen gage the flange 25 fbut it is in a}positionto do so if the. arm29'is drawn toward the magnet30. Thearmature 29 'isYspring-actuated L0 so i to normally assume the position as in Figure 3. l/Vhenever the current is suspended in the magnets 30, the armature 29 assumes the position shown in Figure 3 the arm 26 having glided over the flange 25 without-gripping the same.

bye rm 26 .1 e ng 2 re u ing f om the action of the magnet 30 produces a r volution 'o f the drum2i and the pinion23; connected therewith, *It w'vill befobs'ervedthat 1 this movement is always inone direction, pro ducing 'thereby a constant or one-way revolu tion for the Wheel 19 and the crank 20 con- I ict'd therewith when activated. 7

. rt-win be observedth'at as the crank swings abovelthe horizontal, the casing 17 is moved in. one direction'whereas when the crank is swung below the horizontal, the casing is swung in the opposite direction, the extremes .ofthe two travels being at opposite sides of the pivotal mounting outhest'andard 10. The

rod 9 is over-balanced by the {Weight of "the casing 17 and associated parts with'the result that the dam-per door "12 is opened or closed 'to increase or diminish the draft onthe furnace. i

The electrical energy imparted to the magnets corresponds with the movement of the thermostatic blade '31, which is mounted in a casing 32'locat'ed in any convenient position ata point removed from the furnace.

Tl he blade. travels between the. switch, contacts 33 and 3%. The said contacts are in cirfc uit with lines 3 5 and 36 respectively. These in a e c nnected? h in i P 3 and'SS respectively. The binding posts 37 and 38 are in electrical contact with. the spring -bla des.39 and 40, shown bestin Figure 85 'olf 'the drawings. 1 The ends of the blades i tinue"currentreceived throughthe'said'blades 39 and 40 rest normallyupon'the metalbushing 4 1through which current is conveyed to the casing-17 andthrough the casing 17 to the wir ea and magnets 30,.

Mounted upon the bushing 41 is an insulat in-g sect-or 4:3. "The-sector 43 is in the path of the blades 4Q,-and operates to disconalternately thereby inserting'a'half complete revolution of the gear 19 and of'the crank 20.

' The device is best operated by analtermating currentemploying a belltransf ormer w I Qneo'f the terminals in the; transformer Ae is connected by meansof awire 45 with thefcasing' 2 The. other terminal; ofith'e transformer is connectedby'meansof the wire with a bi'ndiiig post efiiwhich in turn is the magnets 30. 7

connected by means of a wire 48 with the magnets 30. a

/Vhen the partsare arranged as above described and as shown in the drawings, the operation is as follows: I

Presuming that the thermostatic blade has been carried into contact witlithe switch 34,

the current is thereby established through the line 36, binding post 38, the blade 40, the bushingll, casing 17, Wire 42, magnets 30, wire' l8, binding post 47, wire-46, trans- Lformer 44:, Wire 45, thus completing the circuit. The circuit being thus completed, the armature 29 israpidly attracted to and released from the magnets 30in correspondence with'the phases of the alternating current employed. As the armature29 is thus'vi 'brated the arm 26 is swung'to and from the magnet with the result that the drum 24- is vl moved thereby as many revolutions as" is necessaryfor the pinion 23 to rotate the gear wheel 19 until the insulating sector 43 passes under the blade 40,. or in other words,'u nt;il

the gear wheel '19 has made a half complete revolution. The sector 4.3 thus breaking the circuit, the casing 17 and' partsconnected therewith are brought to a stand.

If this operation has opened the door'l2',

V the parts will soremainuntil the tempera ,ture blade 31 may contact with the switch34;

When the heatis'above the predetermined point, the blade 31 is moved to contact with the "switch,33, with the result that now the blade. 39 and electricalpartsj'connected'therewithj are energized. The blade 39 now rest ing on the metallic portion or" the "bushing 41, the magnets 30 are operated as above de-- scribed until the sector 43 in the course of its travelflpasses under the blade 39,. thereby arresting the flow of current and the operation ofthemagnets30. I

While Ifhav'e herein shown and described the apparatus as employing alternating current, it will be understood" that a direct and/or battery current could be used, :e mploying any suitablecontact breaker OI oscillater in conjunction therewith to attain the it ob jecteof vibratingany current excitation in I} claim r 1. In draft 'regulatingmapparatus"for "fur; Y names, 7 the combinationwith a pivotal ly balanced member operatively connected with afurnace draft 'regulatinfgfmember, an ap- ,parat'us; for rocking said balanced member comprising an filHtOHlG tliie Weight. member weight'member being adapted to move fsuc:

supported bysai'd balanced 'meniber,' said cessively in oppositedirections toaffectthe i balance of said balance nemb' gb w ghof-sa id weight memb c I Races, the combination with a 'pivojtiilly. be]

- 2. v Indraftfregulating apparatus for fun anced member ope'ratively connected with a draft regulating member; an apparatus for rocking said balanced member comprising a weight member supported by said balanced member and embodying means carried by said weight member for moving said weighted member successively in opposite directions 'to affect the rocking moment of said balanced member by the weight of said weight member.

3. In draft regulating apparatus for furnaces, the combination with a pivotally balanced member operatively connected with a draft regulating furnace door, anapparatus for rocking said balance-cl member, said apparatus comprising, a weight member movably mounted upon said balanced member for travel thereonto opposite sides of the pivot thereof, electro-mechanical means for movlng said weight member reciprocatively upon said balanced member, said means embodying an electro-magnet and vibratory.

armature therefor, suitable gearing for moving said weighted member, and means attached to said armature for operatively engaging said gearing when and as said armature ismoved by said magnet.

4. In draft regulating apparatus for furnaces, the combination with a pivotally bal-' anced member operatively connected with a draft regulating furnace door, an apparatus for rocking said balanced member, said apparatus comprising, a weight member mov-. ably mounted upon said balanced member for travel thereon to opposite sides of the pivot.

thereof, electro-mechanical means for moving said weight member reciprocatively upon said balanced member, said means embodying, a crank and shaft therefor mounted upon said weighted member, means connecting said crank and stationary member in a manner to necessitate the movement of said weight member when said crank is moved about said shaft, a gear train operatively connected with said shaft to rotate the same, an electro-magnet and vibratory armature therefor mounted in said weight member, and means attached to said armature for operatively engaging said gears when and as said armature is moved by said magnet.

5. In draft regulating apparatus for furnaces, the combination with a pivotally balanced member operatively connected with ashaft, a gear train operatively connected with said shaft to' rotate the same, an electro-- magnet and vibratory armature therefor mounted in said weight member, means attached to said armature for operatlvely engaging said gears when and assaid armature is moved by said magnet, and means for supplying current to said magnet, said means embodying a plurality of supply switches,-

andmeans associated with said shaft for j breaking the contact of one of said switches in correspondence with the half revolution of said shaft and crank attached thereto.

6; Indraft regulating apparatus for furnaces, the combination'with a pivotally bal anced member operatively connected with a draft regulating furnace door, an apparatus for rocking said balanced member, said apparatus comprising, a weight member movably mounted upon said balanced member for travel thereon to opposite sides of the pivotthereof, electromechanical means for moving said weight member reciprocatively upon a said balanced member, said means embody ingaa crank and shafttherefor mounted upon said Weight member, means connecting said crank and stationary member in a manner to necessitate the movement of said weighted member when said crank is moved about said shaft, a gear train operatively connected with said shaft to rotate the same, an electromagnet and vibratory armature therefor mount ed in saidweight member, means attached 7 to said armature for operatively engaging said gears when and as said armature is; moved toward said magnet, meansattached to said armaturefor-operatwely engaging said gear's'when and as said armature is moved by said magnet, and for supplying current to said magnet, said means embody ing a plurality of supply switches, means associated with said shaft for breaking the con- I tact of one of said switches in correspondence with the half revolution Of-Sfild shaft and crank attached thereto, and means for interrupting the current supplied to said magnet.

WINFRED N. LURCOTT. 

